An internal combustion engine is provided with an air cleaner apparatus for supplying clean air to a combustion chamber of the engine. Such an air cleaner apparatus is comprised of a cleaner case, a cover and a cleaner element enclosed by the cleaner case and the cover. A typical example of such an air cleaner apparatus is disclosed in Japanese Patent Application Laid-Open Publication No. 2006-112359 (JP 2006-112359 A). The disclosed air cleaner apparatus will be described in detail below with reference to FIGS. 4 and 5 hereof.
As shown in FIG. 4, an air cleaner apparatus 100 is comprised of a cleaner case 102, a cover 103 closing an upper opening of the cleaner case 102, and a cleaner element 101 enclosed by the case 102 and the cover 103.
The cleaner case 102 has a tongue part 107 designed to be hooked onto a support pin 104, a claw part 108 designed to be hooked on a claw hooking part 105, and a seal holding member 109 that bites into a seal member 106 to thereby provide seal between the cover 103 and the cleaner case 102.
With this arrangement, air within the air cleaner apparatus 100 is filtered by the cleaner element 101 and fed through an opening 111 to the engine.
Referring now to FIG. 5, an operation of the air cleaner apparatus 100 will be described next. For attachment of the cover 103, the tongue part 107 is brought into engagement with the support pin 104, as shown by arrow (1). Then, as shown by arrow (2), the claw part 108 is lowered until it passes through the claw hooking part 105 and hooked on the latter.
The air cleaner apparatus 100 shown in FIGS. 4 and 5 is of the type in which the cover 103 is secured to the cleaner case 102 by means of the claw part 108 and the claw hooking part 105.
Apart from this type of air cleaner apparatus, there is an air cleaner apparatus of another type in which attachment is effected by means of a bolt and a nut, as shown in FIG. 6. In the air cleaner apparatus 120 of FIG. 6, a cleaner case 121 has a support pin 104 at one end and a nut 122 at an opposite end. The cover 123 has a bolt hole 124 in which a bolt 125 is threadedly engaged. To sum up, in the air cleaner apparatus 120, the cover 123 is secured to the cleaner case 121 by means of the tongue part 107 and the bolt 125.
As can be appreciated from FIGS. 4 and 6, there are several different modes of attachment of cleaner covers to cleaner cases. Cleaner covers are aesthetic parts and should have an appealing appearance. End users of air cleaners may wish to replace the cleaner cover 103 of FIG. 4 with the cleaner cover 123 of FIG. 6. There has been developed no technique that can cope with such a situation.